1. Field of the Invention
This invention relates generally to the field of growth factors and specifically to Connective Tissue Growth Factor (CTGF) and the gene encoding this factor.
2. Related Art
Growth factors are a class of secreted polypeptides that stimulate target cells to proliferate, differentiate and organize in developing tissues. The action of growth factors is dependent on their binding to specific receptors which stimulates a signalling event within the cell. Examples of some well-studied growth factors include platelet-derived growth factor (PDGF), insulin-like growth factor (IGF-I), transforming growth factor beta (TGF-.beta.), transforming growth factor alpha (TGF-.alpha.), epidermal growth factor (EGF), and fibroblast growth factor (FGF).
PDGF is a cationic, heat-stable protein found in the alpha-granules of circulating platelets and is known to be a mitogen and a chemotactic agent for connective tissue cells such as fibroblasts and smooth muscle cells. Because of the activities of this molecule, PDGF is believed to be a major factor involved in the normal healing of wounds and pathologically contributing to such diseases as atherosclerosis and fibrotic diseases. PDGF is a dimeric molecule consisting of an A chain and a B chain. The chains form heterodimers or homodimers and all combinations isolated to date are biologically active.
Studies on the role of various growth factors in tissue regeneration and repair have led to the discovery of PDGF-like proteins. These proteins share both immunological and biological activities with PDGF and can be blocked with antibodies specific to PDGF.
These new growth factors may play a significant role in the normal development, growth, and repair of human tissue. Therapeutic agents derived from these molecules may be useful in augmenting normal or impaired growth processes involving connective tissues in certain clinical states, e.g., wound healing. When these growth factors are involved pathologically in diseases, therapeutic developments from these proteins may be used to control or ameliorate uncontrolled tissue growth.
The isolation of these factors and the genes encoding them is important in the development of diagnostics and therapeutics for various connective tissue-related disorders. The present invention provides such an invention.